JAPAN'S OLYMPICS FORECAST : HOT - HOT- HOT

TOKYO'S oppressive mix of heat and humidity may tax athletes and fans.

Japanese summers are known for their oppressive and sometimes deadly mix of heat and humidity. In late July and early August the past two years, more than 1,000 people, including more than 150 in Tokyo, died of heart related causes. Tens of thousands were hospitalized.

That kind of heat led Olympic organizers in 1964 to move the Summer Olympics to October. Those games in Tokyo 55 years ago began in Oct. 10.

Next year, when the Summer Olympics return to Japan's capital, they will open on July 24 and run until Aug.9. It will not take an unusual heat wave to turn them into one one of the hottest Olympics in history, endangering athletes, spectators, workers and volunteers.

Yet in awarding the 2020 Summer Games to Tokyo in 2013, the International Olympic Committee barely considered the weather.

So why was it so important to stage them in the thick of summer?

''It's essentially driven by American television,'' said Dick Pound, a longtime member of the Olympic committee and former chairman of its television negotiations committee.

Officially, the Olympic schedule is dictated by the I.O.C. But because nearly three-quarters of I.O.C. revenues come from the broadcast rights, and about half of those rights are paid by the American broadcaster NBC, the American sports calendar has an outsize impact on Olympic scheduling.

Baseball and football dominate American television in September and October, But July and August are relatively voids.

The last time the Summer Olympics were held outside the July-August window was in 2000, when the Sydney Games were staged in late September. They remain the least watched Summer Games in the United States over the past several decades.
Ever since, the Olympic committee has told candidate cities that the Summer Games must be scheduled between July 15 and Aug 31, barring ''exceptional circumstances.''

The committee offers a scattershot of explanations for that tight window, including a desire to align with the calendars of various sports federations and attract the likes of N.B.A. players in their off-season.

''It's just the question of not having conflicting sports events,'' Thomas Bach, the president of the International Olympic Committee, said in an interview at The New York Times.

But those in and around the Olympics know the power of television in Olympic decision-making.

Television is ''probably the heaviest weighted variable in today's commercial world,'' said Terrence Burns, a consultant who has helped five cities win bids to stage the Olympic Games.

The honor and serving of the latest operational research on Japan's coming Olympics, continues. The World Students Society thanks authors John Branch and Motoko Rich.